Fig. 1

ssDNA morphologies as a function of Au(111) annealing temperature. a Overview of STM images of spray-deposited ssDNA on Au(111) at room temperature, after annealing at 340, 440, and above 500 K, respectively. b STM image of hydrated ssDNA after spray-deposition at room temperature. c Top view of a representative ssDNA structure on Au(111) obtained from MD simulations performed in vacuum at 400 K (see stage 4 in Supplementary Note 3). d STM image of a dehydrated single 20-cytosine ssDNA oligomer after 440-K annealing and the corresponding high- resolution constant-height AFM image, both acquired with a CO-terminated tip. The structural model of c is superimposed on the STM image. e STM image of self-assembled dehydrated ssDNA oligomers after 500-K annealing and the corresponding AFM image. All STM images were recorded at 5 K with I = 2 pA and V = −1.3 V. Properly scaled top views of the representative ssDNA structure are superimposed on b, d, e as a guide for the eye